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作者：Chen, Baojiang; Yi, Grace Y.; Cook, Richard J.
作者单位：University of Washington; University of Washington Seattle; University of Waterloo
摘要：Longitudinal studies of ten feature incomplete response and covariate data It is well known that biases can arise from naive analyses of available data. but the precise impact of Incomplete data depends on the frequency of missing data and the strength of the association between the response variables and emanates and the missing-data indicators Various factors may influence the availability of response and covariate data at scheduled assessment times, and at any given assessment time the resp...
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作者：Ghosh, Sujit K.; Bhave, Prakash V.; Davis, Jerry M.; Lee, Hyeyoung
作者单位：North Carolina State University; North Carolina State University
摘要：Atmospheric concentrations of total nitrate (TNO3), defined here as gas-phase nitric acid plus particle-phase nitrate, are difficult to simulate in numerical air quality models due to the presence of a variety of formation pathways and loss mechanisms, some of which are highly uncertain. The goal of this study is to estimate the relative importance of these different pathways across the Eastern United States by identifying empirical relationships that exist between TNO3 concentrations and a se...
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作者：Ver Hoef, Jay M.; Peterson, Erin E.
作者单位：National Oceanic Atmospheric Admin (NOAA) - USA; Commonwealth Scientific & Industrial Research Organisation (CSIRO)
摘要：In this article we use moving averages to develop new classes of models in a flexible modeling framework for stream networks Streams and rivers are among our most important resources, yet models with autocorrelated errors for spatially continuous stream networks have been described only recently We develop models based on stream distance rather than on Euclidean distance Spatial autocovariance models developed for Euclidean distance may not be valid when using stream distance We begin by descr...
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作者：Gabrys, Robertas; Horvath, Lajos; Kokoszka, Piotr
作者单位：Utah System of Higher Education; Utah State University; Utah System of Higher Education; University of Utah
摘要：The paper proposes two inferential tests for error correlation in the functional linear model, which complement the available graphical goodness-of-fit checks. To construct them, finite dimensional residuals are computed in two different ways, and then their autocorrelations are suitably defined. From these autocorrelation matrices, two quadratic forms are constructed whose limiting distribution are chi-squared with known numbers of degrees of freedom (different for the two forms). The asympto...
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作者：Witten, Daniela M.; Tibshirani, Robert
作者单位：Stanford University; Stanford University
摘要：We consider the problem of clustering observations using a potentially large set of features. One might expect that the true underlying clusters present in the data differ only with respect to a small fraction of the features, and will be missed if one clusters the observations using the full set of features. We propose a novel framework for sparse clustering, in which one clusters the observations using an adaptively chosen subset of the features. The method uses a lasso-type penalty to selec...
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作者：Koyama, Shinsuke; Perez-Bolde, Lucia Castellanos; Shalizi, Cosma Rohilla; Kass, Robert E.
作者单位：Carnegie Mellon University; Carnegie Mellon University; Pennsylvania Commonwealth System of Higher Education (PCSHE); University of Pittsburgh; The Santa Fe Institute
摘要：State-space models provide an important body of techniques for analyzing time series. but their use requires estimating Unobserved states The optimal estimate of the state Is its conditional expectation given the observation histories. and computing this expectation is hard when there are nonlinearities Existing filtering methods, including sequential Monte Carlo. tend to be either inaccurate or slow In this paper, we study a nonlinear filter for nonlinear/non-Gaussian state-space models. whic...
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作者：Wasserman, Larry; Zhou, Shuheng
作者单位：Carnegie Mellon University; Carnegie Mellon University; Swiss Federal Institutes of Technology Domain; ETH Zurich
摘要：One goal of statistical privacy research construct a data release mechanism that protects individual privacy while preset ving information content An example is a random mechanism that takes an input database X and outputs a random database Z according to a distribution Q(n) (vertical bar X) Differential privacy is a particular privacy requirement developed by computer scientists in which Q (vertical bar X) IS required to be insensitive to changes in one data point in X This makes it difficult...
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作者：Taddy, Matthew A.
作者单位：University of Chicago
摘要：This article develops a set of tools for smoothing and prediction with dependent point event patterns. The methodology is motivated by the problem of tracking weekly maps of violent crime events, but is designed to be straightforward to adapt to a wide variety of alternative settings. In particular, a Bayesian semiparametric framework is introduced for modeling correlated time series of marked spatial Poisson processes. The likelihood is factored into two independent components: the set of tot...
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作者：Li, Bo; Nychka, Douglas W.; Ammann, Caspar M.
作者单位：Purdue University System; Purdue University; National Center Atmospheric Research (NCAR) - USA
摘要：Understanding the dynamics of climate change in its full richness requires the knowledge of long temperature time series. Although long-term, widely distributed temperature observations are not available, there are other forms of data, known as climate proxies, that can have a statistical relationship with temperatures and have been used to infer temperatures in the past before direct measurements. We propose a Bayesian hierarchical model to reconstruct past temperatures that integrates inform...
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作者：Choi, Nam Hee; Li, William; Zhu, Ji
作者单位：University of Michigan System; University of Michigan; University of Minnesota System; University of Minnesota Twin Cities
摘要：In this paper. we extend the LASSO method (Tibshittant 1996) for simultaneously fitting a regression model and identifying important interaction terms Unlike most of the existing variable selection methods. our method automatically enforces the heredity constraint that in Interaction term can be included in the model only it the corresponding main terms are also included in the model Furthermore, we extend our method to generalized linear models, and show that It performs as well as if the tru...
